Re: [PATCH v2] arm64: dts: qcom: sa8540p-ride: disable pcie2a node

From: Bjorn Andersson
Date: Tue Jan 30 2024 - 16:29:27 EST


On Tue, Jan 09, 2024 at 10:20:50AM -0500, Lucas Karpinski wrote:
> pcie2a and pcie3a both cause interrupt storms to occur. However, when
> both are enabled simultaneously, the two combined interrupt storms will
> lead to rcu stalls. Red Hat is the only company still using this board
> and since we still need pcie3a, just disable pcie2a.
>

Why are there interrupt storms? What interrupt(s) is(are) involved?

Do you consider this a temporary fix?

Are you okay with pcie3a misbehaving?

Regards,
Bjorn

> Signed-off-by: Lucas Karpinski <lkarpins@xxxxxxxxxx>
> ---
> v2:
> - don't remove the entire pcie2a node, just set status to disabled.
> - update commit message.
>
> arch/arm64/boot/dts/qcom/sa8540p-ride.dts | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/qcom/sa8540p-ride.dts b/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> index b04f72ec097c..177b9dad6ff7 100644
> --- a/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> +++ b/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> @@ -376,14 +376,14 @@ &pcie2a {
> pinctrl-names = "default";
> pinctrl-0 = <&pcie2a_default>;
>
> - status = "okay";
> + status = "disabled";
> };
>
> &pcie2a_phy {
> vdda-phy-supply = <&vreg_l11a>;
> vdda-pll-supply = <&vreg_l3a>;
>
> - status = "okay";
> + status = "disabled";
> };
>
> &pcie3a {
> --
> 2.43.0
>